Nucleic Acids (CH 3.3)

Question 1

What does the Biochemical activity of the cell depend on?

Answer 1

-Production of a large number of proteins that each have their own specific sequence

Question 2

What are the 2 main varieties of Nucleic Acid?

Answer 2

• Deoxyribonucleic Acid (DNA)

- Ribonucleic Acid (RNA)

Question 3

What is the difference between the roles of DNA & RNA?

Answer 3

• Genetic info is stored in DNA

- RNA= copies of genetic info that is then used to direct the synthesis of proteins during gene expression

Question 4

What is the defining characteristic of Nucleic Acids?

Answer 4

-They’re able to serve as templates for producing precise copies of themselves= allows genetic info to be PRESERVED during cell division & reproduction of organisms

Question 5

What is the role of RNA?

Answer 5

• Carries info
• Part of the organelle responsible for protein synthesis
• Involved in the control of gene expression

Question 6

What is Messenger RNA?

Answer 6

• AKA mRNA
• Consists of transcribed, single-stranded copies of portions of the DNA
• The transcripts that mRNA carries are the blueprints that specify the amino acid sequences of proteins

Question 7

What are Nucleic Acids made of?

Answer 7

• Long polymers of repeating subunits= nucleotides
• SO BASICALLY a Chain of 5 carbon sugars linked together by phosphodiester bonds with a nitrogenous base protruding from each sugar

Question 8

What are the 3 basic components for the structure of a Nucleotide?

Answer 8

• 5 carbon sugar/ Pentose if you wanna get fancy. The sugar would be RIBOSE in RNA & DEOXYRIBOSE in DNA
• A phosphate group (polar & negatively charged)
• Organic nitrogenous base (C,H,N,O but mostly nonpolar)

Question 9

What are Polynucleotides?

Answer 9

-Chains of Nucleotides
-Have polarity= A phosphate on the top end and an OH sugar at the bottom end
-Phosphate end being 5’ & the -OH sugar being 3’
(5’ would be at the top)

Question 10

What are the 5 different types of Nitrogenous Bases?

Answer 10

• Adenine
• Cytosine
• Guanine
• Thymine (DNA ONLY)
• Uracil (RNA ONLY)

Question 11

What are the Purines?

Answer 11

• Large, Double ringed molecules found in BOTH DNA & RNA

- Purines= Adenine & Guanine

Question 12

What are Pyrimadines?

Answer 12

• Small, Single ringed molecules
• Cytosine (BOTH DNA & RNA)
• Thymine (DNA ONLY)
• Uracil (RNA ONLY)

Question 13

What do organisms use the sequences of Nucleotides in DNA for?

Answer 13

-To encode the information specifying the amino acid sequences of their proteins

Question 14

How do DNA molecules look like in Eukaryotes?

Answer 14

-2 chains wrapped around eachother in a LONG LINEAR MOLECULE= double helix double stranded

Question 15

How do DNA molecules look like in Prokaryotes?

Answer 15

-Circular moleule

Question 16

How are the 2 strands of DNA connected?

Answer 16

• By base-pair
• The pair consists of a base in one chain attracted by hydrogen bonds of the base pair of the other chain (hydrogenous bonds between nitrogenous bases)

Question 17

What bases pair together?

Answer 17

• Adenine pairs w/ Thymine in DNA or Uracil in RNA

- Cytosine pairs w/ Guanine in DNA & RNA

Question 18

How is RNA different from DNA structurally?

Answer 18

• Designates Ribose as the sugar in it’s sugar-phosphate back bone
• RNA molecules use Uracil amoung its nitrogenous bases (one of its carbons lacks a -CH3 group)

Question 19

How does RNA look like?

Answer 19

-Single stranded

Question 20

What are the different roles of RNA?

Answer 20

• Can carry info= mRNA
• Part of the ribosome= rRNA
• Carries amino acids= tRNA

Question 21

What is the structure of DNA?

Answer 21

• Double stranded, double helix
• Designates Deoxyribose as the sugar in the sugar-phosphate backbone
• Uses Thymine alone its nitrogenous bases

Question 22

What are the 3 most important Nucleotide-containing molecules?

Answer 22

• Adenosine Triphosphate= energy currency for the cell
• Nicotinamide Adenine Dinucleotide (NAD+)
• Flavin Adenine Dinucleotide (FAD)
• Both NAD+ & FAD function as electron carriers in a variety of cellular processes

Question 23

How many bonds are between A & T?

Answer 23

-2 H bonds

Question 24

How many bonds are between C & G?

Answer 24

-3 H bonds

Question 25

How would you tell if a Nucleotide is DNA or RNA?

Answer 25

• Depends on the R group (2’) of the sugar
• If its -OH then its RNA
• If it’s -H then its DNA

Question 26

How do Nucleic acids polymerize?

Answer 26

• By using the sugar & phosphates group of a nucleotide
• When the phosphate & sugar groups polymerize, they make the BACKBONE of the Nucleic acid molecule= Phosphate backbone

Question 27

What is removed to allow Nucleic acids to polymerize & why?

Answer 27

• H from sugar & an OH from phosphate are removed during synthesis
• When these atoms are removed, the bonds between these two groups= Phosphodiester bonds

Question 28

What are the bases attached to in order to stay put in the Nucleic Acid molecule?

Answer 28

-The bases are covalently attached to ribose sugar & that is attached to the phosphate backbone

Question 29

What do the sequence of Bases along w/ the polymer determine?

Answer 29

• Important basis for heredity
• The sequence is written as 5’-3’ bc the opposite direction would have completely different info
• RNA & DNA sequences & their changes are behind evolution & diversity

Question 30

What are are the 4 important polymers?

Answer 30

• Polypeptides/ proteins
• Nucleic Acid (DNA/RNA)
• Complex Carbohydrates
• Tryglycerides & phospholipids

Question 31

What are the 4 important monomers?

Answer 31

• Amino Acids
• Nucleotides
• Simple Sugars
• Fatty acids/ glycerol/ phosphate

Question 32

What are the monomers that make up Polypeptides/Proteins?

Answer 32

-Amino acids

Question 33

What are the monomers that make up Nucleic Acid?

Answer 33

-Nucleotides

Question 34

What are the monomers that make up complex carbs?

Answer 34

-Simple Sugars

Question 35

What are the monomers that make up Triglyceride/phospholipids?

Answer 35

-Fatty acids, Glycerol, Phosphate